Medication Guide App

Nitrofurantoin Pregnancy and Breastfeeding Warnings

Nitrofurantoin is also known as: Furadantin, Macrobid, Macrodantin, Nitro Macro

Nitrofurantoin Pregnancy Warnings

FDA pregnancy category: B Nitrofurantoin should be used during pregnancy only if clearly needed; use of nitrofurantoin is contraindicated at term (38 to 42 weeks gestation), during labor and delivery, and when onset of labor is imminent. Comments: Contraindicated because of possibility of hemolytic anemia due to immature erythrocyte enzyme systems (glutathione instability)

Animal studies have failed to reveal evidence of fetotoxicity or teratogenicity except when administered in very high doses. There are no controlled data in human pregnancy. Nitrofurantoin-induced congenital anomalies have not been reported to date. One retrospective review of 91 pregnancies involving nitrofurantoin use reported no evidence of association to fetal adverse effects. In a review of 229,101 deliveries to Michigan Medicaid patients, there were 1292 first-trimester exposures to nitrofurantoin and 9998 exposures anytime during pregnancy. A total of 52 birth defects (55 expected) was reported with first-trimester exposure and included (observed/expected) 15/12 cardiovascular defects, 1/0 oral clefts, 4/3 polydactyly, 3/2 limb reductions, and 5/3 hypospadias. FDA pregnancy category B: Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

Nitrofurantoin Breastfeeding Warnings

Nitrofurantoin is excreted into human milk. Nitrofurantoin is considered compatible with breast-feeding by the American Academy of Pediatrics, although there is a theoretical risk of hemolytic anemia in neonates and G-6-PD-deficient infants. The manufacturer recommends that due to the potential for serious adverse effects in infants less than one month old, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

A study of 4 lactating women indicated that nitrofurantoin is actively transported into breast milk, achieving a milk-to-serum ratio of 6.21. The infant dose was estimated to be approximately 6% of the maternal dose or 0.2 mg/kg/day (based on a maternal dose of 100 mg nitrofurantoin macrocrystals twice daily).

See Also...

Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Wolters Kluwer Health and is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This drug information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective, or appropriate for any given patient. Multum Information Services, Inc. does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. Copyright 2000-2008 Multum Information Services, Inc. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.